Despite continued increases in the number of approved therapeutics for prevention and treatment of osteoporosis, very little is known about the comparative fracture risk reduction and long-term safety of well-established and newer anti-osteoporosis drugs. Large simple clinical trials (LSTs), also known as pragmatic trials, include randomization but use minimal inclusion/exclusion criteria, allowing for study of 'real world' patient populations who are often excluded in traditional randomized controlled trials. The Active Comparator Osteoporosis Large Simple Trial (ATLAST) will be an LST of patients randomized to FDA approved anti-osteoporosis therapies that will study comparative effectiveness and safety outcomes in diverse community-based populations. As a study design efficiency, ATLAST will include the longitudinal surveillance of patient outcomes through linkage with Medicare medical claims and Part D prescription drug data. To facilitate the successful implementation of a future ATLAST study, we propose a pilot and feasibility testing that focuses on developing and refining the infrastructure and patient enrollment process. We propose to develop and test feasibility of using web- based technology developed in collaboration with Mytrus to be used in busy community physician offices. The specific aims (SAs) of this pilot grant are: SA 1) To develop new and to modify existing materials necessary for the completion of ATLAST including: a) customizing and pilot testing of interactive enrollment, informed consent, and randomization software running on a secure web-based data collection platform, b) obtaining consent and protected health information needed for linkage to Medicare data, and c) developing a patient-based osteoporosis outcomes follow-up survey; SA 2) To complete a mini-clinical trial (i.e. pilot test) of the processes and methods developed for the ATLAST study in partnerships with a sample of six geographically diverse community general practices to test the acceptance and feasibility of informed consent processes, randomization, follow-up surveys, and creation of Medicare finder files in 36 patients. Lessons learned from the ATLAST pilot study will facilitate the full- scale rollout of ATLAST that will provide major advances in community-based LSTs and osteoporosis comparative effectiveness research.